1. Key Laboratory for the Physics and Chemistry of Nanodevices and Center for Carbon-based Electronics, Department of Electronics, Peking University, Beijing 100871, China.
2. Hunan Institute of Advanced Sensing and Information Technology, Xiangtan University, Hunan 411105, China.
3. State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou, 310027, China.
4. Frontiers Science Center for Nano-optoelectronics, Peking University, Beijing 100871, China.